influence of shear wall openings on behaviour of structure

6
INFLUENCE OF SHEAR WALL OPENINGS ON BEHAVIOUR OF STRUCTURE SUMEGH S. PATNE Department of Civil Engineering, Prof. Ram Meghe College of Engineering And Management, Amravati, India [email protected] HARSHAL M. BANUBAKODE Department of Civil Engineering, Prof. Ram Meghe College of Engineering And Management, Amravati, India [email protected] AbstractIn recent decades, shear wall structures are the most appropriate structural forms, which have caused the height of concrete buildings to be soared. In present work, sixteen storey buildings (49.2m) have been modeled using software package ETAB v 9.7.4 for earthquake zone III in India. Different positions and location of shear wall with opening conditions are considered for studying their effectiveness in resisting lateral forces. Study on different opening conditions for storey drift and diaphragm displacement concluded that provision of opening in shear wall ultimately helps to achieve the economy. Index TermsShear wall, lateral forces, storey drift, diaphragm displacement. I. INTRODUCTION A shear wall building is in no way different from an ordinary framed building. However, it differs significantly when it comes to transference of lateral loads. Shear walls are vertical stiffening elements designed to resist lateral forces exerted on a building by wind or earthquakes .Shear walls are vertical elements of the horizontal force resisting system. Shear walls are constructed to counter the effects of lateral load acting on a structure. In residential construction, shear walls are straight external walls that typically form a box which provides all of the lateral support for the building. In the last two decades, shear walls became an important part of mid and high-rise residential buildings. As part of an earthquake resistant building design, these walls are placed in building plans reducing lateral displacements under earthquake loads. So shear-wall frame structures are obtained. Openings are used as architectural needs to have window or doors; besides, engineers want to design buildings without shear lag under negative shear.Shear walls are frequently pierced for doors, windows and corridor openings. II. LITERATURE SURVEY Lin and Kuo (1988), they stated that, had conducted finite element analysis and experimental work to study the ultimate strength of shear wall with openings under lateral load. In test program, the different amount and pattern of reinforcement were arranged around the openings. Torki Harcheganiua et.al. (2011), has stated that, effect of openings dimensions on the relative flexural behavior of adjacent piers (independent or conjugate) in perforated shear walls is addressed. 384 designed models were made and exposed to lateral loads. For middle openings, in addition to the alpha parameter in the literature, the relative flexural behavior of piers in medium-rise buildings can be predicted as function of thickness-to-length ratio of the coupling beam and the ratio of the coupling beam length to the pier length; but in high-rise buildings, it is always conjugate. For corner openings, the alpha parameter must be modified with respect to the number of stories. Rahangdale and Satone (2013), they stated that, shear wall system are one of the most commonly used lateral load resisting in high rise building Shear wall has high in plane stiffness and strength which can be used to simultaneously resist large horizontal loads and support gravity loads. Incorporation of Shear wall has become inevitable in multi- storey building to resist lateral forces. According to them, efficient and ideal location of shear wall of G+5 Storey building in Zone IV is presented with some preliminary investigation which is analyzed by changing various position of shear wall with different shapes for determine parameter like axial load and moments. This analysis is done by using Standard package STADD-pro. Sardar and Karadi (2013), they stated that, shear wall has high in plane stiffness and strength which can be used to simultaneously resist large horizontal loads and support gravity loads. Shear Walls are specially designed structural walls include in the buildings to resist horizontal forces that are induces in the plane of the wall due to wind, earthquake and other forces. They are mainly flexural members and usually provided in high rise buildings to avoid the total collapse of the high rise buildings under seismic forces. The study of 25 storeys building in zone V is presented with some investigation which is analyzed by changing various location of shear wall for determining parameters like storey drift, storey shear and displacement is done by using standard package ETAB. Creation of 3D building model for both linear static and linear dynamic method of analysis and influence of concrete core wall provided at the center of the building.

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Page 1: INFLUENCE OF SHEAR WALL OPENINGS ON BEHAVIOUR OF STRUCTURE

INFLUENCE OF SHEAR WALL OPENINGS ON

BEHAVIOUR OF STRUCTURE

SUMEGH S. PATNE

Department of Civil Engineering,

Prof. Ram Meghe College of Engineering And

Management,

Amravati, India

[email protected]

HARSHAL M. BANUBAKODE

Department of Civil Engineering,

Prof. Ram Meghe College of Engineering And

Management,

Amravati, India

[email protected]

Abstract—In recent decades, shear wall structures are the most

appropriate structural forms, which have caused the height of

concrete buildings to be soared. In present work, sixteen storey

buildings (49.2m) have been modeled using software package

ETAB v 9.7.4 for earthquake zone III in India. Different

positions and location of shear wall with opening conditions are

considered for studying their effectiveness in resisting lateral

forces. Study on different opening conditions for storey drift and

diaphragm displacement concluded that provision of opening in

shear wall ultimately helps to achieve the economy.

Index Terms—Shear wall, lateral forces, storey drift,

diaphragm displacement.

I. INTRODUCTION

A shear wall building is in no way different from an

ordinary framed building. However, it differs significantly

when it comes to transference of lateral loads. Shear walls are

vertical stiffening elements designed to resist lateral forces

exerted on a building by wind or earthquakes .Shear walls are

vertical elements of the horizontal force resisting system. Shear

walls are constructed to counter the effects of lateral load

acting on a structure. In residential construction, shear walls

are straight external walls that typically form a box which

provides all of the lateral support for the building. In the last two decades, shear walls became an

important part of mid and high-rise residential buildings. As

part of an earthquake resistant building design, these walls are

placed in building plans reducing lateral displacements under

earthquake loads. So shear-wall frame structures are obtained.

Openings are used as architectural needs to have

window or doors; besides, engineers want to design buildings

without shear lag under negative shear.Shear walls are

frequently pierced for doors, windows and corridor openings.

II. LITERATURE SURVEY

Lin and Kuo (1988), they stated that, had conducted finite

element analysis and experimental work to study the ultimate

strength of shear wall with openings under lateral load. In test

program, the different amount and pattern of reinforcement

were arranged around the openings.

Torki Harcheganiua et.al. (2011), has stated that, effect of

openings dimensions on the relative flexural behavior of

adjacent piers (independent or conjugate) in perforated shear

walls is addressed. 384 designed models were made and

exposed to lateral loads. For middle openings, in addition to

the alpha parameter in the literature, the relative flexural

behavior of piers in medium-rise buildings can be predicted as

function of thickness-to-length ratio of the coupling beam and

the ratio of the coupling beam length to the pier length; but in

high-rise buildings, it is always conjugate. For corner

openings, the alpha parameter must be modified with respect

to the number of stories.

Rahangdale and Satone (2013), they stated that, shear wall

system are one of the most commonly used lateral load

resisting in high rise building Shear wall has high in plane

stiffness and strength which can be used to simultaneously

resist large horizontal loads and support gravity loads.

Incorporation of Shear wall has become inevitable in multi-

storey building to resist lateral forces. According to them,

efficient and ideal location of shear wall of G+5 Storey

building in Zone IV is presented with some preliminary

investigation which is analyzed by changing various position

of shear wall with different shapes for determine parameter

like axial load and moments. This analysis is done by using

Standard package STADD-pro.

Sardar and Karadi (2013), they stated that, shear wall has high

in plane stiffness and strength which can be used to

simultaneously resist large horizontal loads and support

gravity loads. Shear Walls are specially designed structural

walls include in the buildings to resist horizontal forces that

are induces in the plane of the wall due to wind, earthquake

and other forces. They are mainly flexural members and

usually provided in high rise buildings to avoid the total

collapse of the high rise buildings under seismic forces. The

study of 25 storeys building in zone V is presented with some

investigation which is analyzed by changing various location

of shear wall for determining parameters like storey drift,

storey shear and displacement is done by using standard

package ETAB. Creation of 3D building model for both linear

static and linear dynamic method of analysis and influence of

concrete core wall provided at the center of the building.

Page 2: INFLUENCE OF SHEAR WALL OPENINGS ON BEHAVIOUR OF STRUCTURE

Awdy and Hassan (2013), has been focus on developed to

assess the relative influences of various tensional resisting on

the capacity of open rectangular shear walls. The stability is

considered a four system of loads which produce zero

distortion on cross section of shear wall. Finite element

software ANSYS is used to perform the buckling analysis of

open rectangular shear walls, also theoretical analysis will be

presented for obtaining the critical buckling loads of open

rectangular shear walls. An extensive set of parameters is

investigated including dimensional parameters (walls

thickness, shape factor, mono symmetry, and proportion

factor) and discussions of the results are illustrated.

III. METHODOLOGY

Building models which are consider for analysis in ETAB

v9.7.4 software are given below

Model 1 – Floor plan with the box type shear wall.

Plan Elevation

Model 1(a) - Floor plan with the box type shear wall with

center window openings.

Plan Elevation

Model 1 (b) - Floor plan with the box type shear wall with

door opening

Plan Elevation

Model 1 (c) - Floor plan with the box type shear wall with

eccentric window openings.

Plan Elevation

Model 2 – Floor plan with the center shear wall.

Plan Elevation

Page 3: INFLUENCE OF SHEAR WALL OPENINGS ON BEHAVIOUR OF STRUCTURE

Model 2(a) –Floor plan with the center shear wall with center

window openings.

Plan Elevation

Model 2(b) – Floor plan with the center shear wall with door

openings.

Plan Elevation

Model 2(c) − Floor plan with the center shear wall with

eccentric window openings.

Plan Elevation

Model 3 − Floor plan without shear wall

Plan

Shear wall locations –

Shear walls are used as the main lateral force resisting system

in N-S and E-W directions. In this research 10” thick ordinary

concrete shear walls are used in two locations, at the ends and

at the mid-region of the buildings and their effect on lateral

load distribution and displacement examined.

Analysis data for all the models –

Type of frame: Special RC moment resisting frame

fixed at the base

Seismic zone: III

Number of storey: G + 15

Floor height: 3.0 m

Depth of Slab: 150 mm

Size of beam: (300x 450) mm

Size of column (exterior): (300x 450) mm

Size of column (interior): (300x 450) mm

Spacing between frames: 6 m along x and 6m along

y- directions

Live load on floor: 3 KN/m2

Dead load: 3.75 KN/m2

Floor finish: 1.0 KN/m2

Materials: M 30 concrete, Fe 415 steel Material

Thickness of wall: 230 mm

Thickness of shear wall: 250mm

Density of concrete: 25 KN/m3

Density of infill wall : 20 KN/m3

Type of soil: Medium

Table 1 - Loading combination

SR NO. LOAD COMBINATION

1 1.5 (D.L + L.L )

Page 4: INFLUENCE OF SHEAR WALL OPENINGS ON BEHAVIOUR OF STRUCTURE

2 1.2(D.L + L.L + E.Q.X.)

3 1.2(D.L + L.L - E.Q.X.)

4 1.2(D.L + L.L + E.Q.Y.)

5 1.2(D.L + L.L - E.Q.Y.)

6 1.5 (D.L + E.Q.X )

7 1.5 (D.L - E.Q.X )

8 1.5 (D.L + E.Q.Y )

9 1.5 (D.L - E.Q.Y )

10 0.9 D.L + 1.5 E.Q.X

11 0.9 D.L - 1.5 E.Q.X

12 0.9 D.L + 1.5 E.Q.Y

13 0.9 D.L - 1.5 E.Q.Y

IV. RESULT AND DISCUSSION

Storey Drift -

Storey drift is the displacement of one level relative to the

other level above or below. As per Indian standard, Criteria

for earthquake resistant design of structures, IS 1893 (Part 1) :

2002, the storey drift in any storey due to service load shall

not exceed 0.004 times the storey height.

Figure 1 – Storey drift

Diaphragm displacement -

Diaphragm displacement is the displacement of the diaphragm

with its original position under the lateral effect.

Figure 2 – Diaphragm displacement

a) The following graph showing the diaphragm displacement

of box type shear wall among model 1, 1(a), 1(b), 1(c) and

model 3.

Figure 3- Comparative study for diaphragm displacement

of box type shear wall against storey height.

b) The following graph showing the diaphragm

displacement of center type shear wall among model 2,

2(a), 2(b), 2(c) and model 3.

Page 5: INFLUENCE OF SHEAR WALL OPENINGS ON BEHAVIOUR OF STRUCTURE

Figure 4 - Comparative study for diaphragm displacement of

center type shear wall against storey height.

With the reference of Figure 3 and Figure 4, for box and

centre type shear wall, the diaphragm displacement is

approximately same for all types of opening in shear wall and

with the shear wall without opening. But, the same

comparison with the building without shear wall shows the

importance of the shear wall in a building.

c) The following graph showing the storey drift of corner

type shear wall among model 1, 1(a), 1(b), 1(c) and model 3

.

Figure 5- Comparative study for story drift of box type shear

wall against storey height.

d) The following graph showing the storey drift of center type

shear wall among model 2, 2(a), 2(b), 2(c) and model 3.

Figure 6- Comparative study for story drift of center type

shear wall against storey height.

e) The following graph showing the diaphragm displacement

of box type shear wall with opening among

model1(a),1(b),1(c)

Figure 7- Comparative study for diaphragm displacement of

box type shear wall with opening against storey height.

f) The following graph showing the diaphragm displacement

of center type shear wall with opening among model 2(a),

2(b), 2(c)

Figure 8 - Comparative study for diaphragm displacement of

center type shear wall with opening against storey height.

Page 6: INFLUENCE OF SHEAR WALL OPENINGS ON BEHAVIOUR OF STRUCTURE

V. CONCNLUSIONS

The presence of shear wall can affect the seismic

behavior of frame structure to large extent, and the

shear wall increases the strength and stiffness of the

structure.

The presence of opening in shear wall give

approximately same result as that of the shear wall

without opening. So provision of opening in shear

wall ultimately helps to achieve the economy.

In the comparisons among door opening, center

window opening and eccentric window opening, it is

found that eccentric opening gives more

displacement within the study of diaphragm

displacement and storey drift.

When we provide 11.11% center window opening

and same that for eccentric window opening,

For box and center type shear wall the diaphragm

displacement remain same.

When we provide 22.22% door opening as against

11.11% center window opening, the diaphragm

displacement remain approximately same.

When we provide 22.22% door opening as against

11.11% eccentric window opening, the diaphragm

displacement is more for eccentric window opening

even opening percentage is twice.

REFERENCES

1] C. Y. Lin and C. L. Kuo, “Behaviour of shear wall

with opening”, Proceedings of ninth world

conference on earthquake engineering , Tokyo-

Kyoto, Japan,4 august 2-9, 1988.

2] Meena Shrestha, „Effects Of Openings In Shear Wall

On Seismic Response Of Frame-Shear Wall

Structures‟ M.E. Thesis , Graduate School, Kasetsart

University, 2008

3] M.E. Torki Harcheganiua, B. Talaei Tabab and F.

Farahbod, “Effect of opening dimensions on the

relative flexural operation of coupled shear walls”

4] Ashish S.Agrawal and S.D.Charkha, “ Effect of

change in shear wall location on storey drift of

multistorey building subjected to lateral loads”, ISSN:

2248-9622 2(3), May-Jun 2012.

5] Shahzad Jamil Sardar and Umesh. N. Karadi, “Effect

of change in shear wall location on storey drift of

multistorey building subjected to lateral loads”,

IJISET, 2(9), September 2013.

6] Satpute S. G. and D. B. Kulkarni, “Comparative

study of reinforced concrete shear wall analysis in

multi-storied building with openings by nonlinear

methods”, ISSN 2319 – 6009 2(3), August 2013.

7] Himalee Rahangdale and S.R. Satone, “ Design and

analysis of multistoried building with effect of shear

wall”, ISSN: 2248-9622 www.ijera.com 3(3), May-

Jun 2013.

8] Essam M. Awdy and Hilal A. M. Hassan, “ Capacity

of Open Rectangular Shear Walls”, International

Journal of Engineering Science and Innovative

Technology (IJESIT), 2(1), January 2013.

9] Mazen A. Musmar , “Analysis of Shear Wall with

Openings Using Solid65 Element”, Jordan Journal

of Civil Engineering, 7(2)2, 2013.

10] Anshuman. S. Dipendu Bhunia and Bhavin

Ramjiyani, “ Solution of Shear Wall Location in

Multi-Storey Building”, International Journal Of

Civil And Structural Engineering 2(2), 2011.

11] Mohammad Parsaei Maram and Dr. K Rama Mohana

Rao, “Effect of location of lateral force resisting

system on seismic behavior of RC building”,

International Journal of Engineering Trends and

Technology (IJETT),4(10) - Oct 2013.